BoilerFaultCodesYour boiler's internal computer settings have become scrambled or have fallen outside of their safe operating ranges, causing the system to shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Parameter limits
What causes this fault?
This fault occurs when the boiler's internal memory experiences a software glitch or a physical failure of the electronic circuits. It means the control board can no longer verify its own safety settings, so it shuts down the system to prevent any dangerous operation. The most common cause is a failing Printed Circuit Board (PCB) that has lost its stored configuration data.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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